Method and apparatus for die changing



March 3, 1970 c. L. WARSTLER 3,498,102

METHOD AND APPARATUS FOR DIE CHANGING Filed July 17, 1967 34 FIGZ 38 38 I 27 F IG.3

Ill

INVENTO. 22 1 K14 FIG-5 CLARENCE L.WARS'IELER I 11 4e 44' a ATTORNEYS 3,498,102 METHOD AND APPARATUS FOR DIE CHANGING Clarence Leroy Warstler, Navarre, Ohio, assignor to E. W. Bliss Company, Canton, Ohio Filed July 17, 1967, Ser. No. 653,822 Int. Cl. B21d 37/14 US. Cl. 72-470 Claims ABSTRACT OF THE DISCLOSURE This application discloses improved apparatus for changing dies in forming presses, as well as a method for using such apparatus. The apparatus includes a wheeled die carrier adapted to move die sets into and out of the press on tracks extending across the press bed. Mechanism is'provided to permit the carrier to be connected to the press ram so that upward movement of the ram lifts the die set and carrier away from the tracks. Portions of the tracks in the press bed are removable to permit the carrier to be bottomed out against the press bed when the carrier is subsequently lowered. This provides a firm foundation for the carrier and allows it to remain in the press during press operation.

The present invention is directed to the press art, and more particularly, to an improved method and apparatus for changing dies in forming presses.

The invention is particularly applicable for use in metal working presses and will be described with particular reference thereto; however, it is appreciated the invention is capable of broader application and could be used in substantially any type of press.

In the press art it is common practice to provide metal working presses with movable bolster arrangements to facilitate changing die sets. Normally these arrangements comprised wheeled bolsters or die carriers adapted to ride on tracks extending from outside the press into and across the press bed. The die sets were positioned in mated relationship on the carrier while it was outside the press. The lower die half of the set was bolted to the carrier and the carrier then rolled along the tracks into the press. Once in the press, mechanism functioned to lower the carrier to bring its bottom into engagement with the press bed to provide a firm foundation and relative the load from the carrier wheels. Subsequent to the lowering the press ram was lowered and connected with the upper die half of the die set. The apparatus was then ready for normal press operation. When it was desired to remove a die set from the press, the above operation was reversed, i.e. while in engagement with the lower die half, the upper die half was disconnected from the ram; the carrier was then raised and the carrier and die set rolled out of the press.

Although this general arrangement and mode of operation was satisfactory, it did have certain draw-backs. The primary draw-back was the apparatus required for lowering the carrier into engagement with the press bed and, subsequently, raising it when the dies were to be removed. Normally this apparatus comprised either power actuated lowerable tracks or track sections within the press bed, or power actuated wheel raising mechanisms on the carrier. In both cases, complex mechanisms and relatively large power actuators were required. Consequently, the cost of the installations was substantial.

The present invention provides a simplified movable bolster arrangement and method of operation which does not require complicated mechanisms or power actuators. The simplicity of the invention permits it to be readily applied to many existing presses without any substantial modification thereto.

United States Patent 0 3,498,102 Patented Mar. 3, 1970 In accordance with one aspect of the invention, press apparatus is provided including: a bed having an upwardly facing surface; a frame extending above the bed; a ram carried by the frame for movement toward and away from the bed; power means for driving the ram; a carrier having a lower surface and movable between a first position outside the press and a second position within the press and beneath the ram; support means for supporting the lower surface of the carrier a first distance above the bed surface during movement of the carrier between the first and second positions; means operable when the carrier is beneath the ram for connecting the carrier to the ram whereby upward movement of the ram moves the lower surface a second distance above the bed surface greater than the first distance; the support means include at least a portion thereof movable to a non-supporting position when the lower surface has been moved the second distance above the bed, whereby movement of the ram toward the bed brings the lower surface into engagement with the upwardly facing surface.

By providing an arrangement whereby the press ram can be utilized for lifting the dies and carrier, and the support means moved to a non-supporting position, no complex wheel raising or track lowering mechanisms are needed. Additionally, the press drive furnishes the energy required, thus, elimnating the requirement of power actuators.

In accordance with another aspect, the present invention provides an improvement to the previously discussed method of changing dies in a forming press by the use of a movable die carrier. This improved method includes the steps of: connecting the press ram to the carrier and lifting the carrier and dies by upward actuation of the ram, prior to moving the carrier support means to a nonsupporting position and, subsequently, lowering the dies and carrier and disconnecting the ram from the carrier.

The step of lifting the dies and carrier by the press ram allows the carrier support means to be simple manually movable or removable carrier wheels or track sections, thus, eliminating the need for complex power actuated mechanisms.

A primary object of the present invention is to provide an improved apparatus for changing dies in forming presses.

An additional object is the provision of an improved method of die changing for forming presses.

A further object of the present invention is the provision of die changing apparatus and method which does not require complicated track lowering or wheel raising mechanisms.

Another object is the provision of die changing apparatus and method which can be readily applied to existing presses.

These and other objects and advantages will become apparent from the following description used to illustrate a preferred embodiment of the invention when read in connection with the accompanying drawings wherein:

FIGURE 1 is an elevational view, somewhat diagrammatic, of a press having a movable bolster arrangement constructed in accordance with the present invention;

FIGURE 2 is an enlarged elevational view showing the apparatus of FIGURE 1 being used for changing die sets;

FIGURE 3 is an enlarged elevational view showing the movable bolster in its fina-l located position within the press; and

FIGURES 4 and 5 are detailed views of alternate forms of one of the features of the present invention.

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only and not for the purpose of limiting same, FIGURE 1 shows the overall arrangement of a metal working press A provided with a movable bolster assembly B constructed in accordance with a preferred embodiment of the present invention.

The precise arrangement and construction of press A is not important to the present invention. However, as shown in FIGURE 1, the press is conventional and comprises'a bed provided with four vertically extending uprights 12 which carry an upper ram 14 mounted for vertical reciprocation toward and away from the bed 10. Although only two uprights 12 are shown in the drawings, it is to be understood that a second pair of uprights is positioned directly behind those shown and placed a distance therefrom sufficient to allow the movable bolster B to be rolled between them into and out of the press.

Bolster assembly B includes a carrier comprised of a main horizontally extending frame 22 providing an upper horizontal surface 24 and a lower horizontal surface 26. Upper surface 24 is arranged to receive a die set 27 including a lower die half 27a and an upper die half 27b. Normally the die set is positioned on the carrier when it is outside the press, such as in the dotted line position shown in FIGURE 1. The carrier and die set is then moved to a second position within the press and beneath the ram 14 as shown by solid lines in FIGURE 1. In order to permit the carrier to be readily moved into and out of the press along a guided path, it is provided with support means in the form of four wheels 28 positioned at each corner and connected by brackets 30 with the frame 22. The support means also include a pair of spaced tracks 32 which extend into the press and across the bed 10.

Broadly, the above described structure is well known in the art; however, as previously discussed, in the past it has been the practice to lower the bottom of the carrier into engagement with the press bed by providing mechanisms for lowering the track or sections thereof, or by providing the carrier with raisable wheels. Consequently, after the bolster and die set had been rolled into position beneath the ram the tracks were lowered or the wheels raised to bring the bottom 26 of the carrier into engagement with top surface 11 of the bed. This provided a firm foundation for the lower die and carrier, and relieved the load from the carrier wheels and permitted the forces acting against the lower die half and the carrier during press operation to be transmitted directly to the bed. After the carrier had been lowered against the bed it was clamped thereto and the ram 14 moved down into engagement with the top surface of die half 27b and clamped or bolted to it. The press was then ready for normal operation.

As discussed, these track lowering and wheel raising mechanisms were relatively complex and increased the cost of the installation. Additionally, the track lowering mechanisms took up substantial space in the press bed and could not be added to existing presses without substantial modification to the bed.

According to the present invention means are provided which eliminate the need for track lowering or wheel raising mechanisms. According to the invention, means are provided to permit the ram 14 to be utilized to lift the die set and carrier from its supported position on the support means. Additionally, means are provided to allow at least a portion of the support means to be moved to a non-supporting position when the carrier has been lifted. Consequently, subsequent downward actuation of the ram lowers the carrier and permits its bottom 26 to come into engagement with the top surface 11 of the press bed.

The particular means necessary to perform these functions could take a wide variety of forms. For example, the ram could be connected with the carrier through a plurality of chains temporarily connected between the ram and carrier by the use of hooks and eyes. Additionally, the support means could be moved to a non-supporting position by making the wheels removable or by mounting them so that they could be manually swung into a non- .4 supporting position. There are, of course, a great many possible modifications of apparatus which could perform the required function.

According to the preferred embodiment, the means provided for performing the noted functions include removable connector plates adapted to be removably received on pins 36 and 3-8 extending transversely from the upper and lower die halves respectively. A sufficient number of connector plates and pins are provided to adequately support the weight of the carrier and the lower die. Consequently, after the bolster has been rolled into the press and positioned beneath the ram, the ram is actuated downwardly into engagement with the top surface of upper die half 27b. The ram is then connected to the die half such as by the use of bolts 40. The lower die half has been previously connected to the top surface 24 of carrier frame 22 by bolts 42. The connector plates 34 are then connected on pins 36 and 38, thus completing the interconection between the ram and carrier. Consequently, upward actuation of the ram 14 lifts the bottom of the carrier a second distance above the top surface 11 of the bed, as shown in FIGURE 2. Also, wheels 28 are raised away from tracks 32. Thus, by moving a portion of the supporting means to a nonsupporting position, subsequent lowering of the ram brings the bottom surface 26 of the carrier frame into engagement with the top surface 11 of the bed. This provides a firm foundation for the carrier and lower die during the subsequent press operation.

Although, as previously mentioned, a variety of arrangements could be provided to move a portion of the support means to a non-supporting position, according to the preferred embodiment these means comprise removable track portions 44 provided at the location of each wheel 28 when the carrier is in located position beneath the ram. As shown in FIGURE 4, these removable portions 44 are of a size such as to create a pocket 46 of a size and configuration to permit wheels 28 to be freely and non-supportedly received therein when the bottom of the bolster is in engagement with the top surface of the bed. The members 44 could be of any desired shape or configuration such as shown, for example, in FIGURE 5. Additionally, although it is preferred that members 44 be manually removable to a nonsupporting position, mechanism could, of course, be provided for automatically removing the members from their supporting position after the carrier has been raised.

After the members 44 have been removed and the carrier lowered into engagement with the press bed, the connector plates are removed and the press is then ready for operation as shown in FIGURE 3. In certain instances, the lowered carrier is clamped or bolted to the press bed, however, this is conventional and well known and such clamps or bolts have not been shown. Further, it is to be understood that various types of locating pins, etc. for precisely locating the carrier in position on the bed can be provided.

In order to remove the die set from the press the above operation is reversed. That is: the ram is lowered to bring the upper die half into engagement with the lower half; the connector plates are reinstalled; the carrier and die set are lifted; the members 44 are repositioned; and, the carrier and die set are lowered and disconnected from the ram and rolled out of the press.

As is apparent, the simplicity of the arrangement permits it to be readily applied to existing presses without substantial modification thereto. Note that by merely extending the necessary tracks or guideways provided with the movable or removable sections or portions, substantially any press can be utilized in the described manner.

The invention has been described in great detail suf-. ficient to enable one of ordinary skill in the art to practice the same. Obviously, modifications and alterations of the referred embodiment will occur to others upon a reading and understanding of the specification and it is my intention to include all such modifications and alterations as part of my invention insofar as they come within the scope of the appended claims.

Having thus described my invention, I claim:

1. A forming press including: a bed having an upwardly facing surface; a frame extending above said bed; a ram carried by said frame for movement toward and away from said bed; power means for driving said ram; a carrier having a lower surface and movable between a first position outside the press and a second position within the press and beneath said ram; support means for supporting said lower surface of the carrier a first distance above the bed surface during movement of the carrier between the first and second positions; means operable when said carrier is beneath the ram for connecting said carrier to said ram whereby upward movement of said ram moves said lower surface a second distance above said bed surface greater than said first distance; said support means including at least a portion thereof movable to a non-supporting position when said lower surface has been moved said second distance above said bed, whereby subsequent movement of said ram toward said bed brings said lower surface into engagement with the upwardly facing surface.

2. A forming press as claimed in claim 1 wherein said support means include wheels on said carrier, and tracks extending between said first and second positions on which said wheels are adapted to ride.

3. A forming press as claimed in claim 1 wherein said support means include tracks extending at least between said first and second positions.

4. A forming press as claimed in claim 1 wherein said portion of said support means which is movable to a non-supporting position is horizontally movable.

5. A forming press as claimed in claim 1 wherein said portion of said support means which is movable to a non-supporting position is completely removable from the remainder of said support means.

6. A forming press as claimed in claim 1 wherein said means for connecting said carrier to said ram comprises a die set having upper and lower die halves and means for releasably connecting said upper half to said lower half.

7; A forming press as claimed in claim 1 wherein said support means include tracks and said portions movable to a non-supporting position comprise removable portions in said tracks.

8. In a press including a bed; uprights extending upwardly from said bed; a ram carried by said uprights and movable toward and away from said bed; and a die car rier supported on and movable along tracks from a first position outside said press to a second position within said press and beneath said ram, the improvement comprising; means for connecting said carrier to said ram when said carrier is in said second position, and means permitting at least a portion of said tracks to be moved to a non-supporting postion.

9. The improvement as defined in claim 8 wherein said means permitting at least a portion of said tracks to be moved to a non supporting position comprise removable members in said tracks.

10. In the method of changing die sets in a forming press having a bed and a ram by the use of a carrier provided with support means on which it is movable from a first position outside the press to a second position within the press and beneath the ram; said method including the steps of: positioning a die set comprised of upper and lower halves on said carrier while it is in said first position; moving said carrier and die set to said second position within said press; and, moving said support means to a non-supporting position to lower said carrier into engagement with the bed of said press; the improvement comprising the steps of: (a) connecting said ram to said carrier and lifting said carrier and said die set with said ram prior to moving said support means to said nonsupporting position, and (b) lowering said ram and disconnecting said carrier therefrom subsequent to moving said support means to said non-supporting position.

References Cited UNITED STATES PATENTS 3,134,350 5/1964 Danly et al -299 3,229,791 1/1966 Soman 100-299 3,422,662 1/1969 Geuss 100-299 LOWELL A. LARSON, Primary Examiner US. Cl. X.R. 100-299 

